The Crook Lab works at multiple levels of organization, from cellular neuroscience to behavior, ecology and evolution.

Our broad focus is the physiology of injury.

The Ecology of injury

We are currently studying how minor peripheral injuries change ecologically-relevant behaviors such as foraging and mating. In parallel behavior and neurophysiology experiments, we measure the extent and duration of nociceptive plasticity, which may function to offset injury-related costs.

Effects of serotonin on peripheral and central nociceptor plasticity

In this study we are testing the short- and long-term effects of the neuromodulator, serotonin, on plasticity of nociceptor circuits. Serotonin is well known for its role in memory formation. Here we will test whether application of exogenous serotonin to nociceptive neurons can mimic patterns of cellular plasticity we observe after injury.

Plasticity in the escape Jet circuit

Squid escape from danger by jetting backwards rapidly; a series of giant nerve fibers controls this action. Despite extensive study of the giant axon and synapse of the squid, little is known about its role in natural function. In this project, we ask how injury affects jet escape threshold, and whether the giant axon and synapse are the source of this plasticity.

Effects of early-life injury on long-term neural plasticity

In mammals, injury experienced in early life can result in life-long increase in pain sensitivity. Using squid and octopus, we are testing the hypothesis that this is a highly conserved mechanism that allows animals to adapt to a persistently dangerous environment, where costs of permanent hypersensititvy are outweighed by the benefits of long-term plasticity in nociceptive sensory circuits.

MEASURES OF AFFECTIVE STATE AFTER PERIPHERAL INJURY

Octopuses express complex cognitive behaviors that are readily changed by experience. In this study, we are examining behavioral indicators of affective state after injury, such as learned place avoidance and changes to global risk sensitivity.

CENTRAL NERVOUS SYSTEM PLASTICITY AFTER PERIPHERAL INJURY

The cephalopod CNS is the most complex invertebrate brain, but it is poorly characterized. In this study, we are examining the properties of sensory neuron cell bodies in the central brain, and measuring changes in excitability in cells and circuits in the higher cognitive centers in the supraesophageal ganglion.

ROLE OF THE STELLATE GANGLION IN MODULATING NOCICEPTIVE SENSITIZATION

The stellate ganglion contains the giant synapse that mediates escape jetting, but also contains many other cell bodies. In this study we look at how the stellate ganglion modulates excitability in the peripheral nervous system, by measuring excitability in nerves central and peripheral to the stellate ganglion.

This is a selection of projects currently underway in the crook lab. For more information, contact the lab.

Potential students who wish to work on a specific project or a project of their own design should speak with Dr. Crook, for further information regarding availability, feasibility and funding.